1 //===- llvm/DerivedTypes.h - Classes for handling data types ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the declarations of classes that represent "derived
11 // types". These are things like "arrays of x" or "structure of x, y, z" or
12 // "function returning x taking (y,z) as parameters", etc...
14 // The implementations of these classes live in the Type.cpp file.
16 //===----------------------------------------------------------------------===//
18 #ifndef LLVM_IR_DERIVEDTYPES_H
19 #define LLVM_IR_DERIVEDTYPES_H
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/IR/Type.h"
25 #include "llvm/Support/Casting.h"
26 #include "llvm/Support/Compiler.h"
36 /// Class to represent integer types. Note that this class is also used to
37 /// represent the built-in integer types: Int1Ty, Int8Ty, Int16Ty, Int32Ty and
39 /// Integer representation type
40 class IntegerType : public Type {
41 friend class LLVMContextImpl;
44 explicit IntegerType(LLVMContext &C, unsigned NumBits) : Type(C, IntegerTyID){
45 setSubclassData(NumBits);
49 /// This enum is just used to hold constants we need for IntegerType.
51 MIN_INT_BITS = 1, ///< Minimum number of bits that can be specified
52 MAX_INT_BITS = (1<<24)-1 ///< Maximum number of bits that can be specified
53 ///< Note that bit width is stored in the Type classes SubclassData field
54 ///< which has 24 bits. This yields a maximum bit width of 16,777,215
58 /// This static method is the primary way of constructing an IntegerType.
59 /// If an IntegerType with the same NumBits value was previously instantiated,
60 /// that instance will be returned. Otherwise a new one will be created. Only
61 /// one instance with a given NumBits value is ever created.
62 /// Get or create an IntegerType instance.
63 static IntegerType *get(LLVMContext &C, unsigned NumBits);
65 /// Get the number of bits in this IntegerType
66 unsigned getBitWidth() const { return getSubclassData(); }
68 /// Return a bitmask with ones set for all of the bits that can be set by an
69 /// unsigned version of this type. This is 0xFF for i8, 0xFFFF for i16, etc.
70 uint64_t getBitMask() const {
71 return ~uint64_t(0UL) >> (64-getBitWidth());
74 /// Return a uint64_t with just the most significant bit set (the sign bit, if
75 /// the value is treated as a signed number).
76 uint64_t getSignBit() const {
77 return 1ULL << (getBitWidth()-1);
80 /// For example, this is 0xFF for an 8 bit integer, 0xFFFF for i16, etc.
81 /// @returns a bit mask with ones set for all the bits of this type.
82 /// Get a bit mask for this type.
83 APInt getMask() const;
85 /// This method determines if the width of this IntegerType is a power-of-2
86 /// in terms of 8 bit bytes.
87 /// @returns true if this is a power-of-2 byte width.
88 /// Is this a power-of-2 byte-width IntegerType ?
89 bool isPowerOf2ByteWidth() const;
91 /// Methods for support type inquiry through isa, cast, and dyn_cast.
92 static bool classof(const Type *T) {
93 return T->getTypeID() == IntegerTyID;
97 unsigned Type::getIntegerBitWidth() const {
98 return cast<IntegerType>(this)->getBitWidth();
101 /// Class to represent function types
103 class FunctionType : public Type {
104 FunctionType(Type *Result, ArrayRef<Type*> Params, bool IsVarArgs);
107 FunctionType(const FunctionType &) = delete;
108 FunctionType &operator=(const FunctionType &) = delete;
110 /// This static method is the primary way of constructing a FunctionType.
111 static FunctionType *get(Type *Result,
112 ArrayRef<Type*> Params, bool isVarArg);
114 /// Create a FunctionType taking no parameters.
115 static FunctionType *get(Type *Result, bool isVarArg);
117 /// Return true if the specified type is valid as a return type.
118 static bool isValidReturnType(Type *RetTy);
120 /// Return true if the specified type is valid as an argument type.
121 static bool isValidArgumentType(Type *ArgTy);
123 bool isVarArg() const { return getSubclassData()!=0; }
124 Type *getReturnType() const { return ContainedTys[0]; }
126 using param_iterator = Type::subtype_iterator;
128 param_iterator param_begin() const { return ContainedTys + 1; }
129 param_iterator param_end() const { return &ContainedTys[NumContainedTys]; }
130 ArrayRef<Type *> params() const {
131 return makeArrayRef(param_begin(), param_end());
134 /// Parameter type accessors.
135 Type *getParamType(unsigned i) const { return ContainedTys[i+1]; }
137 /// Return the number of fixed parameters this function type requires.
138 /// This does not consider varargs.
139 unsigned getNumParams() const { return NumContainedTys - 1; }
141 /// Methods for support type inquiry through isa, cast, and dyn_cast.
142 static bool classof(const Type *T) {
143 return T->getTypeID() == FunctionTyID;
146 static_assert(alignof(FunctionType) >= alignof(Type *),
147 "Alignment sufficient for objects appended to FunctionType");
149 bool Type::isFunctionVarArg() const {
150 return cast<FunctionType>(this)->isVarArg();
153 Type *Type::getFunctionParamType(unsigned i) const {
154 return cast<FunctionType>(this)->getParamType(i);
157 unsigned Type::getFunctionNumParams() const {
158 return cast<FunctionType>(this)->getNumParams();
161 /// Common super class of ArrayType, StructType and VectorType.
162 class CompositeType : public Type {
164 explicit CompositeType(LLVMContext &C, TypeID tid) : Type(C, tid) {}
167 /// Given an index value into the type, return the type of the element.
168 Type *getTypeAtIndex(const Value *V) const;
169 Type *getTypeAtIndex(unsigned Idx) const;
170 bool indexValid(const Value *V) const;
171 bool indexValid(unsigned Idx) const;
173 /// Methods for support type inquiry through isa, cast, and dyn_cast.
174 static bool classof(const Type *T) {
175 return T->getTypeID() == ArrayTyID ||
176 T->getTypeID() == StructTyID ||
177 T->getTypeID() == VectorTyID;
181 /// Class to represent struct types. There are two different kinds of struct
182 /// types: Literal structs and Identified structs.
184 /// Literal struct types (e.g. { i32, i32 }) are uniqued structurally, and must
185 /// always have a body when created. You can get one of these by using one of
186 /// the StructType::get() forms.
188 /// Identified structs (e.g. %foo or %42) may optionally have a name and are not
189 /// uniqued. The names for identified structs are managed at the LLVMContext
190 /// level, so there can only be a single identified struct with a given name in
191 /// a particular LLVMContext. Identified structs may also optionally be opaque
192 /// (have no body specified). You get one of these by using one of the
193 /// StructType::create() forms.
195 /// Independent of what kind of struct you have, the body of a struct type are
196 /// laid out in memory consecutively with the elements directly one after the
197 /// other (if the struct is packed) or (if not packed) with padding between the
198 /// elements as defined by DataLayout (which is required to match what the code
199 /// generator for a target expects).
201 class StructType : public CompositeType {
202 StructType(LLVMContext &C) : CompositeType(C, StructTyID) {}
205 /// This is the contents of the SubClassData field.
212 /// For a named struct that actually has a name, this is a pointer to the
213 /// symbol table entry (maintained by LLVMContext) for the struct.
214 /// This is null if the type is an literal struct or if it is a identified
215 /// type that has an empty name.
216 void *SymbolTableEntry = nullptr;
219 StructType(const StructType &) = delete;
220 StructType &operator=(const StructType &) = delete;
222 /// This creates an identified struct.
223 static StructType *create(LLVMContext &Context, StringRef Name);
224 static StructType *create(LLVMContext &Context);
226 static StructType *create(ArrayRef<Type *> Elements, StringRef Name,
227 bool isPacked = false);
228 static StructType *create(ArrayRef<Type *> Elements);
229 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements,
230 StringRef Name, bool isPacked = false);
231 static StructType *create(LLVMContext &Context, ArrayRef<Type *> Elements);
232 template <class... Tys>
233 static typename std::enable_if<are_base_of<Type, Tys...>::value,
235 create(StringRef Name, Type *elt1, Tys *... elts) {
236 assert(elt1 && "Cannot create a struct type with no elements with this");
237 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...});
238 return create(StructFields, Name);
241 /// This static method is the primary way to create a literal StructType.
242 static StructType *get(LLVMContext &Context, ArrayRef<Type*> Elements,
243 bool isPacked = false);
245 /// Create an empty structure type.
246 static StructType *get(LLVMContext &Context, bool isPacked = false);
248 /// This static method is a convenience method for creating structure types by
249 /// specifying the elements as arguments. Note that this method always returns
250 /// a non-packed struct, and requires at least one element type.
251 template <class... Tys>
252 static typename std::enable_if<are_base_of<Type, Tys...>::value,
254 get(Type *elt1, Tys *... elts) {
255 assert(elt1 && "Cannot create a struct type with no elements with this");
256 LLVMContext &Ctx = elt1->getContext();
257 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...});
258 return llvm::StructType::get(Ctx, StructFields);
261 bool isPacked() const { return (getSubclassData() & SCDB_Packed) != 0; }
263 /// Return true if this type is uniqued by structural equivalence, false if it
264 /// is a struct definition.
265 bool isLiteral() const { return (getSubclassData() & SCDB_IsLiteral) != 0; }
267 /// Return true if this is a type with an identity that has no body specified
268 /// yet. These prints as 'opaque' in .ll files.
269 bool isOpaque() const { return (getSubclassData() & SCDB_HasBody) == 0; }
271 /// isSized - Return true if this is a sized type.
272 bool isSized(SmallPtrSetImpl<Type *> *Visited = nullptr) const;
274 /// Return true if this is a named struct that has a non-empty name.
275 bool hasName() const { return SymbolTableEntry != nullptr; }
277 /// Return the name for this struct type if it has an identity.
278 /// This may return an empty string for an unnamed struct type. Do not call
279 /// this on an literal type.
280 StringRef getName() const;
282 /// Change the name of this type to the specified name, or to a name with a
283 /// suffix if there is a collision. Do not call this on an literal type.
284 void setName(StringRef Name);
286 /// Specify a body for an opaque identified type.
287 void setBody(ArrayRef<Type*> Elements, bool isPacked = false);
289 template <typename... Tys>
290 typename std::enable_if<are_base_of<Type, Tys...>::value, void>::type
291 setBody(Type *elt1, Tys *... elts) {
292 assert(elt1 && "Cannot create a struct type with no elements with this");
293 SmallVector<llvm::Type *, 8> StructFields({elt1, elts...});
294 setBody(StructFields);
297 /// Return true if the specified type is valid as a element type.
298 static bool isValidElementType(Type *ElemTy);
300 // Iterator access to the elements.
301 using element_iterator = Type::subtype_iterator;
303 element_iterator element_begin() const { return ContainedTys; }
304 element_iterator element_end() const { return &ContainedTys[NumContainedTys];}
305 ArrayRef<Type *> const elements() const {
306 return makeArrayRef(element_begin(), element_end());
309 /// Return true if this is layout identical to the specified struct.
310 bool isLayoutIdentical(StructType *Other) const;
312 /// Random access to the elements
313 unsigned getNumElements() const { return NumContainedTys; }
314 Type *getElementType(unsigned N) const {
315 assert(N < NumContainedTys && "Element number out of range!");
316 return ContainedTys[N];
319 /// Methods for support type inquiry through isa, cast, and dyn_cast.
320 static bool classof(const Type *T) {
321 return T->getTypeID() == StructTyID;
325 StringRef Type::getStructName() const {
326 return cast<StructType>(this)->getName();
329 unsigned Type::getStructNumElements() const {
330 return cast<StructType>(this)->getNumElements();
333 Type *Type::getStructElementType(unsigned N) const {
334 return cast<StructType>(this)->getElementType(N);
337 /// This is the superclass of the array and vector type classes. Both of these
338 /// represent "arrays" in memory. The array type represents a specifically sized
339 /// array, and the vector type represents a specifically sized array that allows
340 /// for use of SIMD instructions. SequentialType holds the common features of
341 /// both, which stem from the fact that both lay their components out in memory
343 class SequentialType : public CompositeType {
344 Type *ContainedType; ///< Storage for the single contained type.
345 uint64_t NumElements;
348 SequentialType(TypeID TID, Type *ElType, uint64_t NumElements)
349 : CompositeType(ElType->getContext(), TID), ContainedType(ElType),
350 NumElements(NumElements) {
351 ContainedTys = &ContainedType;
356 SequentialType(const SequentialType &) = delete;
357 SequentialType &operator=(const SequentialType &) = delete;
359 uint64_t getNumElements() const { return NumElements; }
360 Type *getElementType() const { return ContainedType; }
362 /// Methods for support type inquiry through isa, cast, and dyn_cast.
363 static bool classof(const Type *T) {
364 return T->getTypeID() == ArrayTyID || T->getTypeID() == VectorTyID;
368 /// Class to represent array types.
369 class ArrayType : public SequentialType {
370 ArrayType(Type *ElType, uint64_t NumEl);
373 ArrayType(const ArrayType &) = delete;
374 ArrayType &operator=(const ArrayType &) = delete;
376 /// This static method is the primary way to construct an ArrayType
377 static ArrayType *get(Type *ElementType, uint64_t NumElements);
379 /// Return true if the specified type is valid as a element type.
380 static bool isValidElementType(Type *ElemTy);
382 /// Methods for support type inquiry through isa, cast, and dyn_cast.
383 static bool classof(const Type *T) {
384 return T->getTypeID() == ArrayTyID;
388 uint64_t Type::getArrayNumElements() const {
389 return cast<ArrayType>(this)->getNumElements();
392 /// Class to represent vector types.
393 class VectorType : public SequentialType {
394 VectorType(Type *ElType, unsigned NumEl);
397 VectorType(const VectorType &) = delete;
398 VectorType &operator=(const VectorType &) = delete;
400 /// This static method is the primary way to construct an VectorType.
401 static VectorType *get(Type *ElementType, unsigned NumElements);
403 /// This static method gets a VectorType with the same number of elements as
404 /// the input type, and the element type is an integer type of the same width
405 /// as the input element type.
406 static VectorType *getInteger(VectorType *VTy) {
407 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
408 assert(EltBits && "Element size must be of a non-zero size");
409 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits);
410 return VectorType::get(EltTy, VTy->getNumElements());
413 /// This static method is like getInteger except that the element types are
414 /// twice as wide as the elements in the input type.
415 static VectorType *getExtendedElementVectorType(VectorType *VTy) {
416 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
417 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits * 2);
418 return VectorType::get(EltTy, VTy->getNumElements());
421 /// This static method is like getInteger except that the element types are
422 /// half as wide as the elements in the input type.
423 static VectorType *getTruncatedElementVectorType(VectorType *VTy) {
424 unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
425 assert((EltBits & 1) == 0 &&
426 "Cannot truncate vector element with odd bit-width");
427 Type *EltTy = IntegerType::get(VTy->getContext(), EltBits / 2);
428 return VectorType::get(EltTy, VTy->getNumElements());
431 /// This static method returns a VectorType with half as many elements as the
432 /// input type and the same element type.
433 static VectorType *getHalfElementsVectorType(VectorType *VTy) {
434 unsigned NumElts = VTy->getNumElements();
435 assert ((NumElts & 1) == 0 &&
436 "Cannot halve vector with odd number of elements.");
437 return VectorType::get(VTy->getElementType(), NumElts/2);
440 /// This static method returns a VectorType with twice as many elements as the
441 /// input type and the same element type.
442 static VectorType *getDoubleElementsVectorType(VectorType *VTy) {
443 unsigned NumElts = VTy->getNumElements();
444 return VectorType::get(VTy->getElementType(), NumElts*2);
447 /// Return true if the specified type is valid as a element type.
448 static bool isValidElementType(Type *ElemTy);
450 /// Return the number of bits in the Vector type.
451 /// Returns zero when the vector is a vector of pointers.
452 unsigned getBitWidth() const {
453 return getNumElements() * getElementType()->getPrimitiveSizeInBits();
456 /// Methods for support type inquiry through isa, cast, and dyn_cast.
457 static bool classof(const Type *T) {
458 return T->getTypeID() == VectorTyID;
462 unsigned Type::getVectorNumElements() const {
463 return cast<VectorType>(this)->getNumElements();
466 /// Class to represent pointers.
467 class PointerType : public Type {
468 explicit PointerType(Type *ElType, unsigned AddrSpace);
473 PointerType(const PointerType &) = delete;
474 PointerType &operator=(const PointerType &) = delete;
476 /// This constructs a pointer to an object of the specified type in a numbered
478 static PointerType *get(Type *ElementType, unsigned AddressSpace);
480 /// This constructs a pointer to an object of the specified type in the
481 /// generic address space (address space zero).
482 static PointerType *getUnqual(Type *ElementType) {
483 return PointerType::get(ElementType, 0);
486 Type *getElementType() const { return PointeeTy; }
488 /// Return true if the specified type is valid as a element type.
489 static bool isValidElementType(Type *ElemTy);
491 /// Return true if we can load or store from a pointer to this type.
492 static bool isLoadableOrStorableType(Type *ElemTy);
494 /// Return the address space of the Pointer type.
495 inline unsigned getAddressSpace() const { return getSubclassData(); }
497 /// Implement support type inquiry through isa, cast, and dyn_cast.
498 static bool classof(const Type *T) {
499 return T->getTypeID() == PointerTyID;
503 unsigned Type::getPointerAddressSpace() const {
504 return cast<PointerType>(getScalarType())->getAddressSpace();
507 } // end namespace llvm
509 #endif // LLVM_IR_DERIVEDTYPES_H